Official Eorzea Census 2016
http://ff14net.2chblog.jp/archives/50236197.html
Some key points --
A9S 82,078 cleared players.
A10S 67,240 cleared players.
A11S 38,614 cleared players.
A12S 19,725 cleared players.
Assuming the unofficial census's lodestone parse of ~357,000 currently active level 60 characters is accurate, that's a ~5.5% clear rate as of now.
DRK is now the most played tank at 47%. WAR is second at 34% and PLD is now last at 29%. That's a huge turn around from a year ago when PLD was the most played.
SCH is the most played healed at 43%. WHM is second with 36%. AST is last at 22%.
SMN is the most played DPS job at 20%. BLM is the next highest at 16%. BRD is at 15%, DRG and MNK are tied at 14%, and NIN and MCH are the two least played DPS jobs at 12% and 8% respectively.
PotD Floor 200 has a 13.1% clear rate amongst characters who've progressed past 100.